Obviously no ones familiar with the expansive clay soils we have here in Missouri. Very familiar with being smartasses tho! We have two and three inch cracks in our lawns here and I have a few older installs with cracks opening up inthe middle of patios and walks.

I guess I'm naive to the situation. But I would assume the same reason asphalt driveways (I understand they are a type of uni-piece for lack of better word) don't just split apart, but when we run into heavy clay we probably use 5-10" of 3/4 clean before our modified base with a geo textile fabric. I don't see that causing a failure in a base that big. Are you having this happen to patios you have installed?

(also I did replace those dead pavers, but told the homeowner I would only this once)

Wow I can't believe some of the responses especially with those
who claim too know it all!
Our soil conditions here range from sand to rock near the city but in the outlying region to the east of ottawa is mostly a heavy clay soil. So back to the original question, yes we are seeing the paver jobs (on occasion) split, just as if you took a shovel and separated the joints. One of my jobs in particular split from half way down the driveway up to the front door, this was during the drought of 2008. We also had an asphalt driveway split almost the full length in June of the same year only 2 weeks after it installed and the owner hadn't even parked on it (they were on holidays) this year we are or were in a drought situation and are seeing this happening again. Over the years we have had to replace approx 5 or 6 asphalt driveways. When the ground dries and shrinks it will shift and anything above it will be affected even with the use of geo tex. If you find the answer to how to prevent this from happening then please share it with me! I switched the type of Poly sand I use from permacons sp(which cracks and stays open if the brick moves) to the envirobond which stays flexible, it's not the answer but it helps to hide the effectPosted via Mobile Device

Thank you zedosix for your response. I really was just wondering if anybody else was experiencing the same problems. I'm telling my customers to wait until we get back to normal moisture levels and see what happens. I don't really think it would be wise to attempt a repair now. They seem to understand that these are unprecedented conditions.